Free Cooling

Potential savings thanks to Free Cooling

In temperate climes north and south of the equatorial zone, the energy-saving advantages of the STULZ CyberAir 3 DX with Indirect Dynamic Free Cooling or Direct Free Cooling can be exploited to the full.

Regions suitable for Free Cooling

Indirect Dynamic Free Cooling

Up to 60 % savings on running costs with Indirect Dynamic Free Cooling

The electronically controlled GE refrigeration system combines compressor cooling and Free Cooling in four stages:

Control based on outside temperature and heat load in the Data Center, without fixed Free Cooling starting temperature with networking of all active components: air conditioning units including standby units, control valves, compressors, EC fans, pumps and dry coolers

Mixed modeIf the fan reaches maximum speed and Extended Free Cooling is no longer sufficient, the compressor is switched on for support; outside air damper open; compressor runs in partial load mode.

DX modeThe unit works in Compressor mode; outside air damper closed.

STULZ developed the CyberAir-3 AMD unit to enable Direct Free Cooling in medium-sized to large Data Centers. These units are equipped with an external damper system, which regulates circulating air, outside air and supply air to ensure the most efficient operation possible. To prevent pressure drops in Free Cooling mode and so increase energy efficiency still further, STULZ has developed the CyberAir AMD with fold-away heat exchanger. In Direct Free Cooling mode, the heat exchanger swivels out of the airflow, enabling the conditioned outside air to flow without losses into the cavity under the raised floor.

The CyberAir AMD can be equipped with the STULZ mixing and filtration box. These STULZ units are perfectly coordinated – for optimized operation. The size of the STULZ mixing and filtration box means that pressure drops are reduced and energy efficiency is enhanced.

Free Cooling with filter frost protectionCompressor off. Outside air mixed with return air is conveyed through the filter directly into the unit, then into the Data Center. The inclusion of return air offers increased frost protection for outside filters.

Free Cooling with inclusion of return airCompressor off. Outside air mixed with return air is conveyed through the filter directly into the unit, then into the Data Center.

Free CoolingCompressor off. Outside air is conveyed through the filter directly into the unit, then into the Data Center.

Mixed modeTo exploit the potential of Free Cooling to the full, the compressor is switched on for support; outside air damper open; compressor running in partial load mode.